1. Field of the Invention
The present invention relates to a modular condensation and thermal compression apparatus for use in power extraction systems.
More particularly, the present invention relates to a modular condensation and thermal compression apparatus for use in power extraction systems, where the modular apparatus or subsystem includes a plurality of heat exchangers, a plurality of pumps, a plurality of throttle control valves, and at least one separator, where the apparatus is designed to efficiently condense and thermally compress an in-coming, low pressure, multi-component working fluid to produce a high pressure, out-going, liquid, multi-component working fluid and where a composition of the in-coming fluid is the same as a composition of the out-going fluid. The present invention also relates to a method where an in-coming, low pressure, vapor multi-component working fluid is converted into a high pressure, out-going, liquid multi-component working fluid in a modular condensation and thermal system.
2. Description of the Related Art
Power systems with thermodynamical power cycles utilizing multi-component working fluids can attain a higher efficiency than power systems utilizing single-component working fluids. Multi-component working fluids condense at variable temperatures. Such working fluids, unlike single component working fluids, have a thermodynamical potential to perform useful work even when sent into a condenser after expansion in a turbine.
Therefore, in the prior art, several power systems that utilized a multi-component working fluid, were designed to have condensation occur in special subsystems which were referred to as distillation condensation subsystems. In this application, such a subsystems will be referred to as a Condensation and Thermal Compression Subsystems (CTCSS), a term that more accurately describes the nature of such subsystems. Such subsystems all work on the following principle: A stream of working fluid subject to condensation enters into the CTCSS at a pressure which is substantially lower than the pressure required for the complete condensation of such a stream at a given ambient temperature. The stream of working fluid is mixed with a recirculating stream of lean solution (i.e., a stream with a substantially lower concentration of the low-boiling component), forming a new stream which can be fully condensed at the given ambient temperature, (referred to as the “basic solution”). Thereafter, the basic solution stream is pumped to a pressure which is slightly higher than the pressure required for the condensation of the working fluid, and is subjected to partial re-vaporization, for which heat that was released in the process of condensation is utilized. Then, the partially vaporized basic solution stream is separated into a lean liquid stream having a reduced concentration of the low-boiling component and a rich vapor stream having a higher concentration of the low-boiling component. The lean liquid stream is then mixed with the condensing stream of working solution (as described above), while the rich vapor stream is combined with a portion of the basic solution stream to reconstitute the initial composition of the working fluid, which is then fully condensed.
In U.S. Pat. No. 4,489,563, the most basic and elementary CTCSS has been described. In this very simple CTCSS, heat from rich vapor stream and lean liquid stream produced by partial re-vaporization is not recuperated, drastically reducing the efficiency of this simple CTCSS.
In other prior art including U.S. Pat. Nos.: 4,548,043; 4,586,340; 4,604,867; 4,763,480; 5,095,708; and 5,572,871, more complicated and elaborate CTCSSs were disclosed. However, all of these prior art CTCSS have one common drawback. In order to increase efficiency via better heat recuperation, they require multiple separate heat exchangers. In many cases, the complexity and high price of such CTCSS are not justified by the increased efficiency that the CTCSS provides.
Thus, there is a need in the art for a Condensation and Thermal Compression Subsystem (CTCSS) that has improved efficiency off-setting the additional cost.